Created By : Abhinandan Kumar

Reviewed By : Rajashekhar Valipishetty

Last Updated : May 17, 2023


Strain is a geometrical deformation measurement that represents the relative displacement between particles in a material body. Strain is a unitless term that is usually expressed as a percentage of the strain value multiplied by 100. In this free online strain tool, we describe each term related to strain.

Change in length
Original length

What Does the Term Strain Mean?

The strain is a dimensionless quantity used to calculate solid deformation. It is defined as the ratio of the material's change in length to its original length. To put it another way, strain is the change in the shape of an object as a result of a force applied to it. Different types of strains can be defined, such as

Normal Strain: Normal strain is the ratio of an object's change in dimension to its original dimension.

Shear Strain: The angular distortion between two mutually perpendicular planes is known as shear strain.

Volumetric Strain: The ratio of the change in volume of an object to its original volume is known as volumetric strain.

The strain formula is given by Strain = ΔL/L

  • Where,
  • ΔL = change in the length of the object
  • L = original length of the object.

What is the definition of Engineering Strain?

Engineering strain is defined as the ratio of change in length to the original length before the application of load/force. The instantaneous length is the difference between the length after a load is applied and the initial length before the load is applied. Engineering strain is expressed as (li-l0)/l0 or Engg strain = (Instantaneous length-Initial length)/Initial length.


How to Use the Strain Calculator?

The following is the procedure how to use the strain calculator:

  • Step 1: In the input field, type the original length, the change in length, and x for the unknown.
  • Step 2: To get the result, click the "Calculate the Unknown" button.
  • Step 3: Finally, in the output field, the object's strain will be displayed.

FAQs on Strain

1. Are displacement and strain the same thing?

The term "displacement" refers to a particle's change in position. The displacement of particles from their original position to a new position is also referred to as a strain.


2. What is the longitudinal strain formula?

The formula of longitudinal of strain;

Longitudinal strain = Change in length / original length.


3. What is engineering strain?

Engineering strain is a unitless quantity that is commonly expressed as a percentage of the strain value multiplied by 100. In practice, engineering strain is used in conjunction with engineering stress.


4. State engineering strain formula?

The formula of engineering strain is;

Engg_strain = (Instantaneous length-Initial length)/Initial length

𝜀 = (li-l0)/l0


5. What is shear strain?

Shear strain is defined as the total amount of deformation perpendicular to a given line rather than parallel to it and is the ratio of displacement to an object's original dimensions due to stress. A shear strain occurs when opposing forces are applied to an object's surface in a parallel direction.